Timber clamp



G; B. BOSCQ TIMBER cum Jan. 7, 1930.

Filed Jan. 9, 1928 Patented Jan. 7, 1930 UNITED STATES PATENT. OFFICE GEORGE 1B. BOSCO, OF CHICAGO, ILLINOIS TIMBER CLAMP Application filed January 9, 1928. Serial No. 245,469.

ularly adapted for clamping together the two struts of an adjustable shore; to provide an improvedclamp of this kind which is adapted to be supported on one of the struts in position to slidably embrace the other strut; to provide improved gripping means for adjustablyvsecuring the clamp to said other strut; and to provide gripping means of this kind which is adapted to increase in its gripping power with an increase in the load sustained by the struts.

clamp, showing also portions of the struts to which it is applied. 7

Fig. 2 is a similar view taken from the opposite side of the shore and showing also the adjusting tool.

Flg. 3 1s a vertical section, taken on the line 33 of Figure 4:.

Figure 1 is a top plan of the shore.

Figure 5 is a detail in side elevation, showing the wedge retracted preparatory to placing the inner strut within the clamp.

. A timber clamp to which this invention'is a li ed is adapted for securing together timbers of various kinds, but, in the specific embodiment herein illustrated, the improved 5 clamp is applied-tothe struts of an adjustable shore.

.In the form shown, the shore, to which" the improved clam is applied, comprises a pair of telescoping timbers or strutsl and o 2 adapted to be clamped together by, an improved clamp 3 and adapted for initial adjustment by means of an adjusting tool 4:.

The strut 1 comprises preferablv a post of standard construction, such as a 4 x 4 timber. The post 2 comprises a pair of bars 5 and 6 arranged in substantially parallel spaced relation and connected together at their lower extremities by cross pieces 7 Adjacent the other end of the strut 2, the bars 5 and 6 are secured to the improved clamp The bars 5 and 6 are preferably 2 x 4 timelgers and the bar 5 is slightly longerthan the In the form shown, the clamp 3 com rises a fitting, preferably a metal casting, which is supported on the strut 2 and which is provided with a central opening 8 for receiving the post 1, to which the fitting is adapted to be locked by improved gripping means arranged at one side of the opening 8.

The fittmg 1s preferably an lntegral casting which, in the form shown, comprises a w pair of side members 9 and 10, arranged in substantially parallel spaced relation and connected together at one end by an anglebar 11, which forms a shelf for enga in the upper extremity of the bar 6. i The side members 9 and 10 are connected together at the opposite end thereof by end pieces 12 and 13 which engage the outer face of the bar 5. The fitting may be rigidly secured to the strut bars 5 and 6 by bolts 14, or other suitable fastening means which extend throu h the side members 9 and 10;

Formed on the end member 12, is a bear-'1 ing shoe 15, which overlies the upper extremity of the strut bar 5, and which is adapted for engagement with the adjusting tool 1 for the purpose of obtaining a fine initial adjustment of the struts, as hereinafter described.

Formed in theside members 9 and 10, are slots 16 and 17, respectively, which are substantially triangular in shape and arranged to provide a keyway for a Wedge 18. The slot 17 is smaller than the slot 16, so as to accommodate the reduced end of the wedge,

The wedge 18 isfulcrumed in the outer corners of the slots 16 and 17 so as to permit the inner edge of the wedge to swing into and out of engagement with the opposed face of the post 1. Formed on the inner edge of the wedge 18, is a substantially fiat bearing surface 19 adapted to abut against'the post 1, when the wedge is driven into its operative position. Formed on respectively opposite sides of the bearing surface '19, are tapered ridges 20 and 21 adapted to bite into the post 1. The ridges 20 and 21 are arranged so that, when the Wedge is initia y drive; 111- duced end, is a shoulder 22 adapted to rest on the lower edge of the slot 17 when the wedge is partly withdrawn from its keyway,

as shown in Figure 5, so as to facilitate the insertion of the post 1 into the opening 8.

Formed on the wedge 18 -adjacent it reduced end, is a shoulder 23 adapted to engage the side member 10 to secure the wedge against withdrawal when the Wedge occupies the retracted position shown in Figure 5. Formed on the wedge adjacent the shoulder'23, is alug 24, located in'the'plane of the wedge and adapted tof'engage theside member 10 for securing-the wedge against withdrawal when it-foccupies its operative position. Theslot 17 is sufliciently wide, adjacent its upper edg to clear the lug 24, as shown in Fig. 5, so as to enable the wedge to be shifted to its retracted position.

The tool 1, by which the. shore may be initially. adjusted, comprises a supporting member in the form of a substantially U shaped stirrup having a pair of sidemembers 25 connected together by an end member '26. The stirrup embraces the post 1 and is provided with aremovb'le locking pin 27 securing it against withdrawal. Pivotal'ly mounted on the side members 25, is an operating lever 28 having-a 'cam 29 adapted to engage the bearing shoe l5 forlifting the strut 1.

In operation, a rough adjustment of the shore is obtained by manuallylifting the strut 1 to approximately the required height. The

tool 4 is then moved downwardly on the post 1 until the cam 29 rests on the bearing shoe 15. By lowering the lever arm 28-, the'strut 1 may be lifted further to obtain the line adjustment. After the shore has been adjusted, the wedge 18 is driven into its keyway,

' causing :both of-=i the ridges 20 and '21 to initially bite into the post 1 and then causing the bearing surface 19 to liefiat against the post, thereby retracting the ridge 20 and leav- 7 ing only the ridge 21 embedded."

Although but one specific embodiment of this invention has been hereinshown and described, it will-:be understood that certain details of the constructionshownmay-be altered or omitted without departing from the spirit of this invention as defined by the following claims.

I claim r 1. A clamp of the class described comprising axfitting having an opening extending ltherethrough for receiving'a timber and havg. a away-leaned 'e'n'oi 'e sear said openthere through for receiving a timber and having a keyway located on one side of said opening, a wedge fulcrumed in said keyway so as to be swingable into different planes, said wedge being tiltable toward said opening for gripping the timber and being tiltable in the "opposite direction to a retracted position for releasing the timber, and a shoulder on said wedge adapted to engage apart of said fitting for holding said wedge in said retracted position.

3. A clamp of the class described comprising a. fitting having an opening extending therethrough for receiving a timber and having a keyway located on one side of said opening, a wedge fulcrumed in said keyway, said wedge being tiltable toward said opening for gripping the timber and being tiltable in the opposite direction to a retracted position for releasing the timber, and a shoulder onsaid wedge adapted to engage a part of "said fitting for holding said wedge in said retracted positionwhen said wedgeis partly withdrawn from said keyway, saidfshoulder being disengaged fro'm'said'fitting part by the-longitudinal movement of said wedge into said keyway.

4-1; A clamp of the class described'comprising a fitting having aniopeni'ng extending therethrough for receiving a timber and having a keywaylocated on one side of said opening, a wedge fulcrumed in said keyway, said wedge being tiltable into one position for gripping the timber and being tiltable into a retracted position for releasing the timber, a lug located on one end of said wedge and adapted to engage'a part of said fitting for securing said wedge against withdrawal from said keyway when said wedge occupies said one position, and a shoulder located adjacent said lug for engagement with said fitting to secure said wedge against withdrawal from:-

saidkeyway when said wedge occupies its retracted position. 7

5. A device of the classdescribed comprisinga pair of s de members arrangedin substantiallyparallel spaced relation and adapted to embracea timber, a pair of end members connecting said side members: together, said end members having partsprojecting inwardly toward-each. other to form shelves for engaging heextremityz f a i truta d grinnin ios means on said side members for engagement with the timber.

6. A device of the class described comprising a pair of posts of different lengths arranged in substantially parallel spaced relation, a strut slidably arranged between said posts, a fitting comprising an integral casting embracing said posts and strut, said fitting having a keyway at one side thereof, a wedge arranged in said keyWay and adapted to grip said strut, a shelf located adjacent said key- Way and engaging an extremity of the shorter of said posts, a shelf formed on the opposite side of said fitting and engaging an extremity of the longer of said posts, and means for securing said fitting to said posts.

Signed at Chicago this 6th day of J anuary, 1928.

GEORGE B. BOSCO. 

